• International Journal of Aeronautical and Space Sciences
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• v.5 no.2
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• pp.28-34
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• 2004

One of the major problem encountered in nuclear plants and satellites design isEMI (Electro-Magnetic Interference) and EMC (Electro-Magnetic Compatibility).Here, our focus is to implement the test board for checking SEU (Single EventUpsets); the effects of protons on the electronic system. The SEU results from thelevel change of stored information due to photon radiation and temperature in thespace environment. The impact of SEU on PLD (Programmable Logic Devices)technology is most apparent in ROM/SRAM/DRAM devices wherein the state ofstorage cell can be upset. In this paper, a simple and powerful test techniques issuggested, and the results are presented for the analysis and future reference. In ourexperiment, the proton radiation facilitv (having the energy of 50 MeV with a beamcurrent of 60 uA of cyclotron) available at KIRAMS (Korea Institute of RadiologicalMedical Sciences) has been applied on a commercially available SRAM manufacturedby Hynix Semiconductor Company.

• Proceedings of the KIPE Conference
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• 2017.07a
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• pp.30-31
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• 2017

본 논문은 인터리브드 준공진 플라이백 컨버터에 추가회로 없이 적용된 최적의 밸리 스위칭 기법을 제안한다. 인터리브드 준공진 플라이백 컨버터는 스위치 양단 전압(Drain-Source voltage)$V_{DS}$이 최소화 되는 지점에서 스위치 턴 온이 되어 전체 시스템의 효율이 향상되고, EMI (Electro Magnetic Interference)와 EMC (Electro Magnetic Compatibility)의 영향을 최소화시킬 수 있다. 제안한 기법은 MCU (Micro Controller Unit) 기반 소용량 컨버터에 간단한 수식을 이용하여 최적의 밸리 스위칭 기법을 가능하게 한다. 제안한 기법은 시스템의 가격과 부피 상승 없이 효율을 향상시키고, EMI와 EMC의 영향을 최소화시킨다. 제안하는 기법의 성능은 시뮬레이션을 통해 확인하였다.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.558-560
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• 2004

Studies on the controlled switching method have been done to prevent the power system surges which cause the insulation deterioration and electro magnetic compatibility (EMC) problems during closing and opening of a circuit breaker. The controlled switching method controls the closing and tripping time in coincidence with the voltage or current to suppress switching surge. It is used to switch condenser bank, no load transformer, and shunt reactor. In this study, basic concept of the controlled switching is introduced, and also the test is performed to find parameters of the controlled switching in a 24kV vacuum circuit. And then, the control device hardware using TMS320C31 DSP has been designed and manufactured. It has been found that the application of IT technology to a circuit breaker is very effective to depress the switching surge.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.05a
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• pp.245-250
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• 1998

각종 전기ㆍ전자기기에서 발생하는 불요 전자파는 노이즈(Noise) 또는 고조파로 불려지고 있는데 이러한 전자파 규제 항목은 크게 두가지(EMI/EMS)로 대분 된다. EMI(Electro magnetic Interference)는 전자파 장해로서 기기 자체에서 발생하는 전자파의 양을 제한하는 것이고 EMS(Electromagnetic Susceptibility)의 경우는 전자파 내성으로서 각종 외부에서 기기 내부로 침입하는 전자기적 에너지에 의하여 기기가 오작동하지 않는 능력을 평가하는 것을 말하며 이 것들을 총칭하여 전자파 적합성(EMC, Electromagnetic Compatibility)라고 정의한다. (중략)

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2407-2418
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• 2023

Internal replaceable electronic module substitutions can impact EMC (ElectroMagnetic Compatibility) qualification testing and results if EMC testing is conducted at the cabinet level. The impact of component substitutions on EMC qualification results therefore should be evaluated. If a qualitative evaluation is not adequate to ensure that the modified product will not impact the cabinet level EMC qualification results, a new qualification testing should be conducted. Component level retesting should be conducted under electromagnetically equivalent conditions with the cabinet level test. This paper analyzes the propagation of conducted susceptibility test waveforms in a representative cabinet and evaluates the impact of component substitutions on cabinet level EMC qualification results according to the location of the replacement items. A guideline for a qualitative evaluation of the impact of component substitutions is described based on the propagation of the conducted susceptibility test waveforms. A module level test method is also described based on an analysis of the shielding effectiveness of the cabinet.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.9
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• pp.805-811
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• 2016

This paper proposes an estimation algorithm of phase currents of inverter systems with the planar bus bars for brush-less DC (BLDC) motors. The planar bus bar can improve the characteristic of the EMC(Electro-Magnetic Compatibility). In these inverters, a single current sensor of the dc-link measures the sum of a smooth capacitor current and phase currents of brush-less DC motor. Thus, it is essential to extract phase currents from the measured single current to control BLDC motor. Therefore, in this paper, the phase current is estimated by analyzing equivalent circuits of the BLDCM in ON and OFF periods of switching elements. The usefulness of the proposed algorithm is verified through experimental results.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.1
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• pp.63-72
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• 2020

As the design complexity and performances are increased in satellite electronic board, noise related problems are also increased. To minimize the noise issues, various design improvements are performed by power integrity and signal integrity analysis in this research. Static power and dynamic power design are reviewed and improved by DC IR drop and power impedance analysis. Signal integrity design is reviewed and improved by time domain signal wave analysis and PCB(Printed Circuit Board) design modifications. And also power planes resonance modes are checked and mitigation measures are verified by simulation. Finally, it is checked that radiated noise is reduced after design improvements by EMC(Electro Magnetic Compatibility) RE(Radiated Emission) measurement results.

• Journal of Applied Reliability
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• v.16 no.4
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• pp.287-294
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• 2016

Purpose: Environment test support is urgent for small and medium defense companies in order to improve the reliability of weapons systems. Also, to reduce the burden of test costs, the voucher system must be strengthened. Quality assurance support should be accompanied by budget support. Methods: First of all, it is necessary to expand infrastructure for test equipment that suffers shortages by considering environmental test frequency and waiting periods to reduce the time required for environmental tests. Results: In regard to the environmental test, expansion for test equipment infrastructure, security of budget for the test, establishment of test plan, education and consulting support are required to resolve some limits of small and medium defense companies. Conclusion: Along with the opening of environmental test courses for industry operators, the expansion for consulting support projects of the defense industry support system is needed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.521-522
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• 2008

21세기를 접하면서 산업전자 분야의 비약적인 발전과 함께 과학문명은 눈부시게 발전해 나아가고 있다. 이것의 원천은 바로 전기(Electric)이다. 우리는 풍요로운 삶 자체를 전기 공급에서 누리고 있으며 또 비극적인 사태를 맞이할 때도 있다. 즉, 전기기기를 이용하면 원하건 원치 않건 전자기파가 발생이 된다 이것이 자연현상이며 전자기파는 IT, BT, CT를 비롯하여 산업 전체에 많은 영향을 미치고 있다. 일반적으로 우리가 말하는 전자기파 장해의 기본 요소는 노이즈원(잡음원), 경로매체, 피해장치 등으로 구성되는 데 잡음원(Noise Source)은 각종 시스템에서 구성되고 있는 전자기 에너지의 발생원으로 볼 수 있으며 이 발생원에서 경로매체(금속:전도성, 대기중:전파성 등)를 통하여 피해장치(전기전자통신기기류)에 방해를 주고 있는 상태를 전자기파 장해라고 설명할 수 있다. 전자기파 잡음원에서 경로를 거쳐 전자기파에 대하여 피해장치가 안정된 상태로 동작하도록 규정하는 용어 즉, 전자파 양립성 또는 적합성 (EMC : Electro Magnetic Compatibility))이란 용어를 가지고 전기 전자 통신기기에서 발생되는 불필요한 전자파와 전자파 내성시험을 만족하도록 의무화하고 있다. EMC 는 EMI (불요 전자파 또는 전자파 간섭 : Electro Magnetic Interference) + EMS (전자파 내성 : Electro Magnetic Susceptibility) 2가지 시험을 함께 전자파 적합성 (EMC) 시험으로 표현되고 있다. 전자파 적합성 시험의 목적으로 EMl는 전도성 또는 전파성에 대한 주파수 대역(잡음)을 보호하기 위한 것이 목적이고 EMS는 프로세서가 내장된 기기류의 오동작을 방지하기 위하여 감응평가를 하는 것이다. 즉, 감응(Susceptibility)이란 어떤 장비나 시스템이 전자기파 장해에 쉽게 영향을 받는 것을 뜻하는 데 전자파 장해를 견디면서 본래의 기능을 충분하게 발휘하며 동작할 수 있는 능력을 말한다.

• Korean Journal of Materials Research
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• v.29 no.9
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• pp.532-541
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• 2019

Information and communication technologies are developing rapidly as IC chip size becomes smaller and information processing becomes faster. With this development, digital circuit technology is being widely applied to mobile phones, wireless LANs, mobile terminals, and digital communications, in which high frequency range of GHz is used. In high-density electronic circuits, issues of noise and EMC(Electro-Magnetic Compatibility) arising from cross talk between interconnects or devices should be solved. In this study, sheet-type electromagnetic wave absorbers that cause electromagnetic wave attenuation are fabricated using composites based on soft magnetic metal powder and silicon rubber to solve the problem of electromagnetic waves generated in wireless communication products operating at the frequency range of 2.4 GHz. Sendust(Fe-Si-Al) and carbonyl iron(Fe-C) were used as soft magnetic metals, and their concentrations and sheet thicknesses were varied. Using soft magnetic metal powder, a sheet is fabricated to exhibit maximum electromagnetic attenuation in the target frequency band, and a value of 34.2dB(99.9 % absorption) is achieved at the target frequency.